Hammerspoon macOS Battery Percentage <=10% Alert

init.lua

local alertShown = false

function checkBatteryStatus()
    local currentCapacitymAh = hs.battery.capacity()
    local maxCapacitymAh = hs.battery.maxCapacity()
    local currentCapacityPercentage = (currentCapacitymAh / maxCapacitymAh) * 100
    local isCharging = hs.battery.isCharging()
    if currentCapacityPercentage <= 5 and not alertShown then
        hs.alert.show("Battery capacity <= 5%!", 500.0) -- 500 seconds duration for the alert
        alertShown = true
    elseif currentCapacityPercentage > 5 or isCharging then
        hs.alert.closeAll() -- Close the alert if capacity is more than 10% or if power is connected
        alertShown = false
    end
end

batteryWatcher = hs.battery.watcher.new(checkBatteryStatus)
batteryWatcher:start()